The Celtics rallied late against the undermanned Magic, but a frantic comeback failed in a 108-104 loss at Amway Arena on Monday night.

Boston had to cancel Jayson Tatum at the last minute shortly before the end due to illness. Al Horford got the start in his place, but the visitors missed Tatum’s offense for much of the evening.

The Celtics were able to build a 15-point lead at halftime thanks largely to their defense, but that lead evaporated in the third quarter. Orlando was red-hot with its shooting in the frame, knocking down 60 percent of its attempts and all seven of its free throws, completely erasing Boston’s lead.

Boston’s offense also faltered in the third period, knocking down just 26.3 percent of their attempts, but they managed to stay afloat offensively at the free throw line.

Ultimately, Boston’s offense stalled in the fourth quarter as the Magic opened the first period with a 7-0 run and limited the Celtics to one of their worst shooting nights of the season from 3-point range. Orlando pushed its lead to as many as 10 points with 3:36 left in the fourth quarter, but the Celtics fought back with a 12-1 run and created several chances to take the lead after Goga Bitadze’s exit in the final minute take over. Ultimately, late misses from Horford and Jaylen Brown and a three-pointer from Tristan da Silva secured victory for the hosts.

Da Silva (18 points) and Jalen Suggs (16 points) led the undermanned Magic, who played without their two stars, Paolo Banchero and Franz Wagner. Jaylen Brown top-scored for Boston with 35 points.

The Celtics return to action on Christmas and host the 76ers at TD Garden.

Here are four Celtics takeaways from Monday’s loss to the Magic:

Referees allow physical exchanges of blows: The Magic have one of the best defenses in the league and knew they had to play with an added level of physicality without their leading scorers against the defending champions. The end result was arguably the most physical games the Celtics have played all season. Orlando made Boston fight for every inch of its offensive movement all night long, with constant ball pressure at the rim and in the paint. Boston struggled to get going on offense all night, mustering just 24 percent shooting from 3-point range and 13 assists. With ball movement restricted on offense, it was difficult to achieve a loose look. The Celtics reached the free throw line quite often, but piled up turnovers (19), which led to an overall subpar offensive night against a feisty Magic team.

Celtics record season low in assists: The Magic’s defense deserves some credit for this, but the Celtics didn’t rely on their offensive principles when it came to ball movement all night. They recorded a season-low 13 assists and 37 made field goals, four fewer than their previous record this year. Boston’s offense completely collapsed on that front in the third quarter, as they had one assist in the entire period and were noticeably lacking Jayson Tatum to help them break through the defense. White and Brown both had four assists, but the rest of the squad combined for five as isolation sequences that led to missed shots occurred far too often.

Celtics fail to find opportunities for 3-point attempts: Few teams have the personnel necessary to give Boston a wide-open 3-point victory, but the Magic were that team all night long. Not only did the Celtics have a miserable night shooting (24.2 percent from 3-point range), but they also couldn’t get perimeter looks at the speed that Joe Mazzulla likes. Boston’s 33 3-point attempts were by far a season low (the previous low was 41). The Magic were able to switch well and get past screens throughout the night, depriving them of the open looks that the Celtics routinely generate against most opponents. Those attempts largely failed that night as Tatum was sidelined and Boston’s offense suffered as a result.

Mazzulla rides the starters hard: With Tatum unavailable and the Celtics trailing in the fourth quarter, Mazzulla returned to his starting five longer than usual in the final frame. The net result was a season high in minutes for Porzingis (37) and a big minutes load for Al Horford (35) off the bench. The decision would have paid off late, as the Celtics used a 12-1 run to give themselves a chance. However, in the final minute, Horford missed an open 3-point attempt, while Brown missed the ensuing possession with a 3-pointer -Speeded shot that ended Boston’s chances. There were few tough situations like this all year where Boston came up short, but it was fascinating to see how they handled it without Tatum. Brown played well most of the night, but the miscues from Boston’s most important ballplayers (15 total turnovers) were ultimately too much for the visitors.

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